Battery Substitution for a A1322

Hello, I have a Mid 2009 Unibody Macbook and i performed this substitution:

- The original A1322 battery (60 Wh)

Substituted with:

- The new A1322 battery (63.5 Wh) that I bought on July, the 27th on the European store.

It started having problems some days ago.

In the last week, the power dropped twice with the battery almost discharged (but not fully discharged).

The MacBook could not detect it and could not go to the hibernation state.

Today the MacBook said that the battery has to be substituted as it is not able anymore to charge it. In particular:

- The MacBook is not able anymore to work using the battery. If the charger is disconnected the MacBook turns off as the battery is not connected.

- When turned on (it is only possible with the charger plugged in) the green led bar flashes and the white led in front of the MacBook flashes too.

I have tried to reset the SMC and the NVRAM but it didn't work.

I have tried to put the old battery again and it works. Of course, it has limited capacity as it very old but seems to be ok: the Mac recognizes it correctly.

So it seems the new battery's fault, which worked well for about 1 month but now is completely unusable.

Any suggestion? Should I talk with the iFixit assistance?

Thank you.